From the given recurrence, it follows that

and so on down to the first term,

(Notice how the exponent on the 2 and the subscript of <em>a</em> in the first term add up to <em>n</em> + 1.)
Denote the remaining sum by <em>S</em> ; then

Multiply both sides by 2 :

Subtract 2<em>S</em> from <em>S</em> to get

So, we end up with

Answer:
EIther 45 or 15
Step-by-step explanation:
<u>The x and y coordinates of the origin is equal to (0, 0), which is the point of intersection of the x-axis and y-axis. The x and y coordinates of a point on the x-axis is of the form (a, 0), and here the y coordinate of the point is equal to zero.</u>
Answer:
7 miles
Step-by-step explanation:
Let's call the distance between the library and police station x. Then, the distance between the police station and fire station would be 3 less than twice x. Twice means multiply by 2 so twice x is 2 * x = 2x and 3 less than means that you subtract 3 so 3 less than 2x is 2x - 3. Now, we know that x = 5 so all we have to do now is substitute x = 5 into 2x - 3, therefore, the answer is 2 * 5 - 3 = 7 miles.
Answer:
A
Step-by-step explanation:
Taking the square root of both sides.